public void Add(Modem modem, string phoneNumber)
{
if (modem == null || phoneNumber == null)
throw new ArgumentNullException();
else if (!IsDialable(phoneNumber))
throw new ArgumentException();
lock (this._DirectoryLock)
{
this._Directory.Add(phoneNumber, new Subscriber(modem));
modem.Dial += OnDial;
modem.Answer += OnAnswer;
modem.Hangup += OnHangup;
}
}
private void DoHangup()
{
Modem peer;
lock (this._StateLock)
{
peer = this._Peer;
this._Peer = null;
this._State = ModemState.Command;
}
if (peer != null)
{
peer.ChannelBreak();
this.Hangup(this);
}
}
private void DoDial(string phoneNumber)
{
Modem peer = null;
ConnectResult result = this.Dial(this, phoneNumber, ref peer);
if (result == ConnectResult.Connect && peer != null)
{
peer.OnOOBReceived(OOBSignal.Ring);
}
Thread.Sleep(1000);
switch (result)
{
case ConnectResult.Connect:
this.ChannelWrite(ConnectMessage);
lock (this._StateLock)
{
this._Peer = peer;
this._State = ModemState.Data;
}
break;
case ConnectResult.NoDialtone:
this.ChannelWrite(NoDialtoneMessage);
break;
case ConnectResult.NoAnswer:
this.ChannelWrite(NoAnswerMessage);
break;
case ConnectResult.Busy:
this.ChannelWrite(BusyMessage);
break;
}
}
private void DoAnswer()
{
Modem peer = null;
if (this.Answer(this, ref peer))
{
lock (this._StateLock)
{
this._Peer = peer;
this._State = ModemState.Data;
this._Ringing = false;
}
}
}
public ConnectResult Connect(string callerPhoneNumber, string dstPhoneNumber, out Modem modem)
{
lock (this._DirectoryLock)
{
Subscriber caller;
Subscriber dst;
if (!this._Directory.TryGetValue(callerPhoneNumber, out caller))
throw new ArgumentException();
if (caller.OffHook)
{
modem = null;
return ConnectResult.NoDialtone; // "NO DIALTONE"
}
caller.OffHook = true;
if (!this._Directory.TryGetValue(dstPhoneNumber, out dst))
{
caller.OffHook = false;
modem = null;
return ConnectResult.NoAnswer; // "NO ANSWER"
}
else if (dst.OffHook)
{
caller.OffHook = false;
modem = null;
return ConnectResult.Busy; // "BUSY"
}
dst.OffHook = true;
caller.Peer = dst;
dst.Peer = caller;
modem = dst.Modem;
return ConnectResult.Connect; // "CONNECT"
} //lock
}
public Subscriber(Modem modem)
{
this.Modem = modem;
this.Peer = null;
}
private void OnHangup(Modem sender)
{
this.Disconnect(sender.PhoneNumber);
}
private ConnectResult OnDial(Modem sender, string phoneNumber, ref Modem peer)
{
return this.Connect(sender.PhoneNumber, phoneNumber, out peer);
}
private bool OnAnswer(Modem sender, ref Modem peer)
{
lock (this._DirectoryLock)
{
Subscriber receiver;
if (!this._Directory.TryGetValue(sender.PhoneNumber, out receiver))
throw new ArgumentException();
if (receiver == null || receiver.Peer == null)
return false;
peer = receiver.Peer.Modem;
}
return (peer != null);
}
